EU leaders emerged from a meeting with the Greek prime minister saying the country needs to come up with a reform plan if it wants more of their money.
They have been saying much the same for weeks - but now it is on a tighter timetable.
The EU leaders said Greek PM Alexis Tsipras committed to providing a list of specific reforms in the coming days that would improve his country's balance sheet.
German chancellor Angela Merkel said the leaders did not discuss specific numbers.
Hanging over the summit of 28 heads of state and government are fears that the hardline of the Greek government formed in January could cause the country to drop out of the euro, something that would trigger a crisis for the currency shared by 19 nations.
Mr Tsipras made a last-minute request for a mini-summit last night with half a dozen senior EU officials.
Those officials agreed to the meeting - over the objections from some of the other leaders, who complained they were being left out.
In addition to Ms Merkel and Mr Tsipras, the meeting included French president Francois Hollande, European Central Bank president Mario Draghi and EU president Donald Tusk.
The leaders emerged more optimistic than when they went in, but gave little evidence of why, other than the timetable of "the next days" for Mr Tsipras to present them with his intended reforms.
"The Greek government will take full responsibility for the reforms and submit a list of these reforms, which will be a comprehensive list of specific reforms, in the coming days,"Ms Merkel said.
Mr Tsipras was upbeat as well.
"We are more optimist after this deliberation," he said. "All the sides confirmed their intention to try their best to overcome the difficulties of the Greek economy as soon as possible."
European leaders have become increasingly exasperated by what many see as foot-dragging on the part of Tsipras' government.
Greece agreed a month ago to push through reforms in exchange for EU help in keeping it solvent, but has delayed submitting the list.
"A deal is a deal," Dutch prime minister Mark Rutte said before the meeting.
Adding to the European frustration, the Greek parliament approved an anti-poverty bill on Wednesday.
It was the first piece of legislation that the government has put through - and it did so without full consultation from its creditor partners.
Greece's economic policies drew criticism even from nations outside the eurozone.
British Prime Minister David Cameron marvelled yesterday at how poorly the Greek economy has fared compared to his own.
"When I first came here as prime minister five years ago, Britain and Greece were virtually in the same boat. We had similar-sized budget deficits," he said.
"The reason we are in a different position is we took long-term, difficult decisions and we had all of the hard work and effort of the British people."
Greece is banking on the fact that its European partners all want to keep the eurozone intact, fearing that if Greece pulls out others might as well.
"Nobody wants a so-called Grexit and everybody wants to avoid this risk," Mr Tusk said.